Usefulness of Combined Bedside Lung Ultrasound and Echocardiography to Assess Weaning Failure From Mechanical Ventilation

Abstract

Recognition of the cardiac origin of weaning failure is a crucial issue for successful discontinuation of mechanical ventilation. Bedside lung ultrasound and echocardiography have shown a potential in predicting weaning failure. Objective of this report was to describe the case of a patient repeatedly failing to wean from mechanical ventilation, where the combined use of lung ultrasound and echocardiography during a spontaneous breathing trial uncovered an unexpected cause of the failure. Case report. General ICU of a university teaching hospital. Single case, abdominal surgery postoperative patient, not predicted to experience a difficult weaning. Cardiovascular therapy adjustments consistent with lung ultrasound and echocardiography findings acquired during spontaneous breathing trials. All patient's standard hemodynamic and respiratory parameters, datasets from comprehensive lung ultrasound and echocardiographic examinations, and pertinent data from biochemistry exams, were collected during two spontaneous breathing trials. Data from beginning and end of each of the two ultrasound monitored weaning trials, and from the end of the successful weaning trial following therapy and the previously failed one, were analyzed and qualitatively compared. Lung ultrasound performed at the end of the failed spontaneous breathing trial showed a pattern consistent with increased extravascular lung water (diffuse, bilateral, symmetrical, homogeneous sonographic interstitial syndrome). Concurrent echocardiography diagnosed left ventricular diastolic failure. Ultrasound findings at the end of the successful weaning trial showed normalization of the lung pattern and improvement of the echocardiographic one. The patient eventually returned to spontaneous respiration and was discharged from the ICU. The use of bedside lung ultrasound and echocardiography disclosed left ventricular diastolic dysfunction as unexpected cardiogenic cause of weaning failure and lead to subsequent correct patient management.